Field of the Invention
The invention is concerned with an improvement in a hydraulic implement which includes a hydraulic pump for controlling flow of a hydraulic fluid to said implement and an electric motor for driving said pump. More particularly the invention is concerned with such improvement as applied to a hydraulic lift cylinder for controlling lift truck accessories such as the extension of a lift truck mast assembly, controlling the tilt thereof and controlling the power steering function of a lift truck.
Previous hydraulic implement controlling assemblies which have included a motor and pump have generally had the motor and the pump noncoaxially aligned and separated a spaced distance apart and have included a coupler of one sort or another for transmitting the rotary motion of the driving shaft of the motor to the driven shaft of the pump. Extremely careful and precise aligning has been necessary to assure that there is no misalignment of the motor and its driving shaft relative to the pump and its driven shaft. Such arrangements have generally taken up a good deal of space since space was required for the coupling. They have also presented serious alignment problems requiring the designing of special couplings. Further, they have required the use of separate bearings on a first or driving end of the driving shaft of the motor and on a first or driven end of the driven shaft of the pump.
It would be highly desirable to provide a motor and pump arrangement for a hydraulic implement which was easy to initially align and which would remain aligned through normal operation of the hydraulic implement and which at the same time would save often valuable space by providing overall a more compact arrangement of the motor and the pump portions thereof. It would be further advantageous if such an arrangement could use a single bearing to support both a first or driving end of a driving shaft of the motor and a first or driven end of the driven shaft of the pump. The present invention provides all of the above mentioned improvements in an easy to machine and inexpensive structure.